DRAFT 

REPORT TO THE ADVISORY BOARD 

ON RADIATION AND WORKER HEALTH

National Institute for Occupational Safety and Health 

COMPARISON OF SC&A’S BLIND DOSE RECONSTRUCTION 

TO NIOSH’S DOSE RECONSTRUCTION OF CASE #[REDACT] 

FROM THE HANFORD SITE AND WELDON SPRING PLANT 

Contract No. 211-2014-58081 

SCA-TR-DRC2015-CN[Redact]

Prepared by 

Douglas Farver, CHP 

S. Cohen & Associates 

1608 Spring Hill Road, Suite 400 

Vienna, Virginia 22182 

June 2015 

Disclaimer

This document is made available in accordance with the unanimous desire of the Advisory Board on 

Radiation and Worker Health (ABRWH) to maintain all possible openness in its deliberations. However, 

the ABRWH and its contractor, SC&A, caution the reader that at the time of its release, this report is predecisional and has not been reviewed by the Board for factual accuracy or applicability within the 

requirements of 42 CFR 82. This implies that once reviewed by the ABRWH, the Board’s position may 

differ from the report’s conclusions. Thus, the reader should be cautioned that this report is for 

information only and that premature interpretations regarding its conclusions are unwarranted.
Effective Date:

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S. Cohen & Associates:

Technical Support for the Advisory Board on

Radiation & Worker Health Review of

NIOSH Dose Reconstruction Program

Document No. 

SCA-TR-DRC2015-CN[Redact]

Effective Date: 

Draft – June 17, 2015

Comparison of SC&A’s Blind Dose 

Reconstruction to NIOSH’s Dose 

Reconstruction of Case #[Redact] from the 

Hanford Site and Weldon Spring Plant

Page 2 of 23

Task Manager:

________________________ Date: ___________

Rose Gogliotti

Supersedes:

N/A

Project Manager:

________________________ Date: ___________

John Stiver, MS, CHP

Reviewer:

 Kathleen Behling

 Rose Gogliotti

 John Stiver

Record of Revisions

Revision 

Number Effective Date Description of Revision

0 (Draft) 06/17/2015 Initial issued.
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TABLE OF CONTENTS 

Abbreviations and Acronyms ..........................................................................................................4

1.0 Relevant Background Information .......................................................................................6

2.0 Comparison of Methodology/Doses used by NIOSH and SC&A for Case #[Redact] ........7

2.1 Occupational External Dose Calculations ...............................................................9

2.1.1 Recorded/Modeled Photon and Neutron External Doses ............................9

2.1.2 Missed/Modeled Photon and Neutron External Doses ..............................11

2.1.3 Occupational Medical Doses .....................................................................12

2.1.4 Onsite Ambient External Dose ..................................................................13

2.2 Occupational Internal Doses ..................................................................................15

2.2.1 Internal Doses from Uranium ....................................................................15

2.2.2 Internal Doses from Recycled Uranium Contaminants .............................16

2.2.3 Internal Doses from Thorium Processing ..................................................18

2.2.4 Internal Environmental Dose .....................................................................19

3.0 Summary Conclusions .......................................................................................................20

References ......................................................................................................................................21

Addendum A: SC&A’s Blind Dose Reconstruction Report of Case #[Redact] ...........................23

LIST OF TABLES

Table 1-1. Comparison of NIOSH’s Assigned Doses to SC&A’s Blind DR Doses ......................7

Table 2-1. Comparison of Data and Assumptions Used by NIOSH and SC&A ............................8

Table 2-2. Recorded Photon Doses .................................................................................................9

Table 2-3. Comparison of Recorded/Modeled Photon and Neutron Doses ..................................11

Table 2-4. Comparison of Missed Photon and Neutron Doses .....................................................12

Table 2-5. Comparison of Occupational Medical Doses ..............................................................13

Table 2-6. Comparison of Onsite Ambient Doses ........................................................................14

Table 2-7. NIOSH Uranium and Decay Product Intakes ..............................................................15

Table 2-8. SC&A Uranium and RU Contaminant Intakes ...........................................................16

Table 2-9. NIOSH Uranium and RU Contaminant Intakes ..........................................................17

Table 2-10. SC&A RU:U Determination......................................................................................17

Table 2-11. RU:U Comparison .....................................................................................................18

Table 2-12. SC&A Thorium Processing Intakes ..........................................................................18

Table 2-13. NIOSH Thorium Processing Intakes .........................................................................19

Table 3-1. Comparison of Total External and Internal Doses ......................................................20
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ABBREVIATIONS AND ACRONYMS 

Advisory Board Advisory Board on Radiation and Worker Health 

Bq Becquerel 

CADW Chronic Annual Dose Workbook 

CATI Computer-Assisted Telephone Interview 

CF correction factor

CW coworker 

DCF dose conversion factor

D.D. deep dose 

DOE (U.S.) Department of Energy 

DOL (U.S.) Department of Labor 

DR dose reconstruction 

EE Energy Employee 

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 

2000

FEMP Fernald Environmental Management Project 

GCF geometric correction factor 

ICD International Classification of Diseases 

ICRP International Commission on Radiological Protection 

IMBA Integrated Modules of Bioassay Analysis 

IREP Interactive RadioEpidemiological Program 

keV kiloelectron volts 

LAT lateral 

LOD limit of detection

μg/L micrograms per liter 

mg/g milligrams per gram 

mg/L milligrams per liter 

MDA minimum detectable activity

MeV million electron volts 

NIOSH National Institute for Occupational Safety and Health 

np neutron-to-photon (ratio) 

ORAUT Oak Ridge Associated Universities Team 
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PA posterior/anterior 

PFG photofluorography 

pCi picocuries 

pCi/day picocuries per day 

pCi/g picocuries per gram 

pCi/mg picocuries per milligram 

POC probability of causation 

ppb parts per billion

rem Roentgen equivalent man 

RU recycled uranium 

SC&A S. Cohen and Associates (SC&A, Inc.) 

SD standard deviation 

SEC Special Exposure Cohort 

TBD technical basis document 

Th thorium 

TIB technical information bulletin

U uranium 

UF uncertainty factor 

WSP Weldon Spring Plant 

yr year 
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1.0 RELEVANT BACKGROUND INFORMATION 

Under Contract No. 211-2014-58081, SC&A was tasked by the Advisory Board on Radiation 

and Worker Health (Advisory Board) to perform six blind dose reconstructions (DRs) at the July 

2014, DR Subcommittee meeting. SC&A was provided all of the Department of Energy (DOE) 

dosimetry records; the Department of Labor (DOL) correspondence, forms, and medical records; 

and the Computer-Assisted Telephone Interview (CATI) Reports that were made available to the 

National Institute for Occupational Safety and Health (NIOSH) for constructing doses in behalf 

of these cases. SC&A used an independent approach to reconstruct occupational external and 

internal doses for the cases using the available dosimetry records and current guidance from 

NIOSH, including the spreadsheets and other tools developed by NIOSH to calculate the doses. 

On February 27, 2015, SC&A submitted to the Advisory Board and NIOSH, a memorandum 

containing the summary results of our blind DR in behalf of Case #[Redact]. The complete DR 

report titled, Blind Dose Reconstruction of Case #[Redact] from the Hanford and Weldon Spring 

Sites (SCA-TR-BDR2015-CN[Redact]), which provides the assumptions and methodologies 

used to derive occupational radiation doses and resultant probability of causation (POC) values, 

is included herein as Addendum A. In this report, SC&A presents a comparison between 

NIOSH’s and SC&A’s DR methodologies, doses, and resultant POC values for Case #[Redact]. 

Table 1-1 summarizes the external and internal occupational doses calculated by SC&A and the 

NIOSH-assigned doses for the liver cancer diagnosed in behalf of Case #[Redact]. A detailed 

comparison of the two methodologies used to calculate doses in behalf of this case is presented 

in Section 2. Section 3 of this report provides Summary Conclusions. 

It should be noted that where appropriate, an explanation is provided regarding the differences in 

doses and why they occurred. However, SC&A does not make any value judgments regarding 

which among them may be the more preferred approach. It is our position that further 

discussions are best addressed by the DR Subcommittee. 
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Table 1-1. Comparison of NIOSH’s Assigned Doses to SC&A’s Blind DR Doses

NIOSH Liver Doses

(rem)

SC&A Liver Doses

(rem)

External Dose (Occupational)

 ▪ Recorded/Modeled:

 30–250 keV Photons 2.227 1.750

 >250 keV Photons 2.093 1.264

 0.1–2 MeV Neutrons 1.839 NA

 ▪ Missed/Modeled:

 30–250 keV Photons 2.010 2.010

 >250 keV Photons 1.890 1.598

 0.1–2 MeV Neutrons 1.661 NA

 ▪ 1957 Coworker Dose:

 30–250 keV Photons NA 0.198

 >250 keV Photons NA 0.143

 ▪ 1957 Onsite Ambient Dose:

 30–250 keV Photons 0.043 NA

 ▪ 1963 Onsite Ambient Dose:

 30–250 keV Photons 0.020 NA

 ▪ 1948 Onsite Ambient Dose:

 30–250 keV Photons 0.038 0.027

 ▪ Occupational Medical Dose:

 PFG exam, 1948 NA 0.690

 30–250 keV Photons 1.602 1.602

Internal Dose (alpha):

 U, RU, Th 6.623 4.065

Total Dose 20.046 13.347

POC 42.49% 40.71%

NA = Not assessed 

2.0 COMPARISON OF METHODOLOGY/DOSES USED BY NIOSH 

AND SC&A FOR CASE #[REDACT] 

Case #[Redact] represents an energy employee (EE) who worked as a [redact] at the Hanford 

Site from [redact], to [redact], and as a [redact] at the Weldon Spring Plant from [redact], to 

[redact]. 

The EE was not monitored for external or internal radiation exposure at the Hanford Site. 

However, the EE was monitored for external photon exposure and internal exposures during 

most of the employment period at the Weldon Spring Plant. The EE was diagnosed with bile 

duct cancer (cholangiocarcinoma) (ICD-9 Code 155.1) on [redact].

For calculating radiation doses from employment at Hanford and the Weldon Spring Plant, both 

DR methods primarily relied on guidance in the technical basis document (TBD) for Hanford 

(issued as six separate documents numbered ORAUT-TKBS-0006-1 through ORAUT-TKBS0006-6), the TBD for the Weldon Spring Plant (ORAUT-TKBS-0028-1 through ORAUT-
Effective Date:

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TKBS-0028-6), and ORAUT-OTIB-0005, Technical Information Bulletin: Internal Dosimetry 

Organ, External Dosimetry Organ, and IREP Model Selection by ICD-9 Code. NIOSH and 

SC&A used the guidance provided in the relevant technical documents, along with the EE’s 

records to reconstruct the EE’s radiation dose. NIOSH used efficiency measures and 

assumptions related to radiation exposure and intakes resulting in an overestimate of the EE’s 

total dose. SC&A employed a best-estimate approach for calculating annual organ doses. 

A summary of the documents, assumptions, and dose parameters used by each DR method is 

provided in Table 2-1: 

Table 2-1. Comparison of Data and Assumptions Used by NIOSH and SC&A 

Parameters NIOSH SC&A

External Dose

Recorded/Missed/Unmonitored:

 Records/Guidance Documents DOE records, ORAUT-TKBS-0028-6 DOE records, ORAUT-TKBS-0028-6

 Work Locations Site wide as [redact] Site wide as [redact]

 Energy Range 

Photons: 50% 30 keV–250 keV

 50% >250 keV

Neutrons: 100% 0.1–2 MeV

Photons: 50% 30 keV–250 keV

 50% >250 keV

Neutrons: NA

 DCF

1.064 (30 keV–250 keV)

1.0 (>250 keV)

1.0 (0.1–2 MeV)

1.064 (30 keV–250 keV)

0.845 (>250 keV)

NA (0.1–2 MeV)

 Dosimeter Uncertainty Factor 1.4 NA

 Dose Distribution Recorded/CW– Constant

Missed – Lognormal

Recorded/CW– Constant

Missed – Lognormal

External Medical X-rays:

 Guidance Documents ORAUT-TKBS-0028-3, OTIB-0079. ORAUT-TKBS-0028-3

 Frequency

PA and LAT chest examinations during 

most years of employment, with two such 

examinations in [redact]. (8 exams)

PA and LAT chest examinations during 

most years of employment, with two such 

examinations in [redact]. (8 exams)

 Dose Data Table 3-3 of ORAUT-TKBS-0028-3 Table 3-3 of ORAUT-TKBS-0028-3

 Dose Distribution Normal; SD = 30%. Normal; SD = 30%.

Onsite Ambient Dose:

 Guidance Documents OCAS-IG-001, ORAUT-TKBS-0006-4, 

ORAUT-TKBS-0028-4 

ORAUT-PROC-0060, ORAUT-TKBS0006-4

 Dose Data ORAUT-TKBS-0006-4, ORAUT-TKBS0028-4Table 4-8 of ORAUT-TKBS-0006-4

 Dose Distribution Constant Constant

Internal Dose

Recorded/Missed/unmonitored:

 Records/Guidance Documents

DOE records, ORAUT-OTIB-0014,

ORAUT-TKBS-0006-4, ORAUT-TKBS0028-4

DOE records, ORAUT-TKBS-0006-4, 

ORAUT-TKBS-0028-4

 Dose Determination Approach Overestimate – chronic through entire 

employment period

Best Estimate – chronic through most of 

employment based on fit of bioassay

 Solubility Type Various, see Section 2.1.1 Various, see Section 2.1.1

POC Program:

NIOSH-IREP POC Ver. 5.7 Ver. 5.7.1
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2.1 OCCUPATIONAL EXTERNAL DOSE CALCULATIONS 

2.1.1 Recorded/Modeled Photon and Neutron External Doses 

The DOE records show that the EE was not monitored while employed at the Hanford Site for 

3 months in [redact]. Dosimetry records were available for the time period the EE was 

employed at the Weldon Spring Plant, [redact] to [redact]. Individual dosimeter results or 

quarterly dosimeter totals are available for [redact]–[redact]. However, no dosimeter results are 

found for [redact]. Monitoring records for the EE begin in [redact]. 

Photons 

SC&A used the EE’s recorded photon dose values that were >LOD/2 of 0.025 rem to assign 

doses using a photon energy range of 50% 30–250 keV photons and 50% >250 keV photons. A 

dosimeter correction factor (CF) of 1.1 (for 30–250 keV photons only) and geometric correction 

factor (GCF) of 2.1 were also included. NIOSH applied the same energy range and GCF, in 

addition to a 1.4 uncertainty factor (UF), but NIOSH did not apply the dosimeter CF of 1.1 for 

30–250 keV photon doses. Also, SC&A applied a 30–250 keV photon dose conversion factor 

(DCF) of 1.064 and a >250 keV photon DCF of 0.845 from OCAS-IG-001. NIOSH used the 

30–250 keV photon DCF of 1.064 and a maximizing DCF of 1.0 for the >250 keV photon doses. 

The recorded photon doses are shown in Table 2-2. 

Table 2-2. Recorded Photon Doses 

Year Photon Energy SC&A Dose 

(rem)

NIOSH Dose 

(rem)

[redact] E=30–250 keV 0.042 0.053

[redact] E=30–250 keV 0.091 0.116

[redact] E=30–250 keV 0.602 0.766

[redact] E=30–250 keV 0.684 0.871

[redact] E=30–250 keV 0.244 0.311

[redact] E=30–250 keV 0.086 0.109

[redact] E>250 keV 0.030 0.050

[redact] E>250 keV 0.066 0.109

[redact] E>250 keV 0.435 0.720

[redact] E>250 keV 0.494 0.819

[redact] E>250 keV 0.177 0.293

[redact] E>250 keV 0.062 0.103

To illustrate the differences between the SC&A and NIOSH calculations, examples of the 

[redact] recorded photon calculations are shown below. 

Records show in [redact], the EE received a deep dose (D.D.) of 0.490 rem. The photon dose 

was assumed to be 50% 30–250 keV and 50% >250 keV. A GCF of 2.1 was applied.

SC&A’s Calculation 

DCFs of 1.064 for 30–250 keV photons and 0.845 for >250 keV photons were applied; along 

with a dosimeter CF of 1.1 for the 30–250 keV photon doses. 
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30–250 keV photon dose = D.D. × DCF × Energy f. × CF × GCF 

= 0.490 × 1.064 × 0.50 × 1.1 × 2.1 

= 0.602 rem 

 >250 keV photon dose = D.D. × DCF × Energy f. × GCF 

= 0.490 × 0.845 × 0.50× 2.1 

= 0.435 rem 

NIOSH’s Calculation 

DCFs of 1.064 for 30–250 keV photons and 1.0 for >250 keV photons were applied, along with 

a UF of 1.4 for both the 30–250 keV and >250 keV photon doses. 

30–250 keV photon dose = D.D. × DCF × Energy f. × GCF × UF 

= 0.490 × 1.064 × 0.50 × 2.1 × 1.4 

= 0.766 rem 

 >250 keV photon dose = D.D. × DCF × Energy f. × GCF × UF 

= 0.490 × 1.0 × 0.50× 2.1× 1.4 

= 0.720 rem 

SC&A multiplied the 30–250 keV photon doses by a factor of 1.1 to account for low-energy 

photons emitted by uranium and thorium at the Weldon Spring Plant in accordance with 

Section 6.3.8 of ORAUT-TKBS-0028-6. According to the NIOSH DR report, “To account for 

uncertainty in dosimeter response, an uncertainty factor of 1.4 was applied to measured photon 

doses.” While this is consistent with Section 6.3.10 of ORAUT-TKBS-0028-6, it is unclear if 

this uncertainty would be applied in a best-estimate DR. 

Neutrons 

The EE did not have any neutron dosimetry data. Based on Section 6.3.4.2 of ORAUT-TKBS0028-6, SC&A did not assess doses from neutron exposure. It states: 

Because the WSP processed very small amounts of slightly enriched uranium 

(<1% 235U and 0.68% of total throughput and no UF6), the exposure to neutrons 

was miniscule [SEC-00143, p. 33]. The fact that the uranium was in the form of 

UF4 and other nonproducing neutron compounds resulted in the total absence of 

recordable neutron doses even though neutron dosimeters were worn by those 

employees working with the enriched uranium... The slightly enriched uranium 

was processed in Buildings 103,105, 201, and 301, so employees assigned to 

these facilities during the processing of this material received neutron dosimeters. 

Studies as reported in ORAUT 2010a [SEC-00143, p. 33 and pp. 59–61] provide 

adequate evidence that there is no technical reason to expect any measurable 

neutron doses and, therefore, no reported results. 

NIOSH assessed unmonitored neutron dose. The NIOSH DR report states: 
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Site-specific information indicates that [the EE] was also likely to have been 

exposed to neutron radiation, which was not monitored by the site during [the 

EE’s] employment [ORAUT-TKBS-0028-6]. Therefore, unmonitored neutron 

dose has been assigned.

The DR report also states that, “while at the Weldon Spring Plant, [the EE] performed 

[redact]on machinery throughout the plant, repaired motors and equipment, and worked on 

[redact].” 

SC&A did not find any statements in the EE’s records or ORAUT-TKBS-0028-6 indicating the 

EE was likely exposed to neutrons. It is uncertain if NIOSH would include the unmonitored 

neutron doses in a best-estimate DR. 

An example of NIOSH’s [redact] neutron calculation is shown below.

Records show in [redact], the EE received a D.D. of 0.490 rem. The neutron energy was 

assumed to be 0.1 to 2.0 MeV with an organ DCF of 1.0, GCF of 2.1, an uncertainty of 1.4 and a 

neutron-to-photon (np) ratio of 0.23. An ICRP-60 CF of 1.91 was also applied. [The liver DCF 

in OCAS-IG-001 for 0.1–2.0 MeV neutrons is 0.641.]

0.1 to 2.0 MeV neutron dose = D.D. × DCF × np × GCF × UF× ICRP 

= 0.490 × 1.0 × 0.23 × 2.1 × 1.4× 1.91 

= 0.633 rem 

Table 2-3. Comparison of Recorded/Modeled Photon and Neutron Doses 

SC&A (rem) NIOSH (rem)

Total Recorded/Unmonitored Photon Dose 3.014 4.320

Total Recorded Neutron Dose NA 1.839

Both DR methods entered doses into the Interactive RadioEpidemiological Program (IREP) as a 

constant distribution with no uncertainty. 

2.1.2 Missed/Modeled Photon and Neutron External Doses 

SC&A assigned only missed photon doses based on information in ORAUT-TKBS-0028-6. 

Both missed photon and neutron doses were assigned by NIOSH. 

Missed Photon Doses 

SC&A analyzed the number of actual zeros and potential zeros based on a biweekly badge 

exchange cycle and arrived at a total of 72 zeros (or <LOD/2 values) for photons. SC&A used 

the annual number of zeros, the LOD/2 value, the DR parameters as listed above, and the 

applicable DCFs to determine the annual missed photon doses. This resulted in the assignment 

of 2.010 rem for 30–250 keV photons and 1.598 rem for >250 photons. 

NIOSH also used 72 zeros to determine the missed photon dose. However, NIOSH used an 

organ DCF of 1.0 instead of 0.845 for the >250 keV photon doses. This resulted in NIOSH 
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assigning a total missed photon dose of 2.010 rem for 30–250keV photons and 1.890 rem for 

>250 keV photons. 

Missed Neutron Doses 

NIOSH used the annual number of zeros, the photon LOD/2, the 95th percentile np ratio of 0.23, 

the GCF of 2.1, ICRP 60 CF of 1.91, and organ DCF of 1.0 to calculate the missed neutron 

doses. An example of NIOSH’s [redact] missed neutron dose calculation is shown below. 

Records show in [redact], the EE’s dosimeter results shown 7 zeros with an LOD/2 of 

0.025 rem.

Missed Neutron Dose (0.1–2.0 MeV) = (# zeros × LOD/2) × DCF × ICRP × GCF× np 

 = (7 × 0.025 rem) × 1.0 × 1.91 × 2.1 × 0.23 

 = 0.161 rem 

Table 2-4. Comparison of Missed Photon and Neutron Doses 

SC&A (rem) NIOSH (rem)

Total Missed Photon Dose 3.608 3.900

Total Missed Neutron Dose NA 1.661

Both DR methods entered missed photon doses into IREP as a lognormal distribution with an

uncertainty of 1.520. NIOSH also entered unmonitored neutron doses as a geometric mean value 

with a geometric standard deviation of 1.520.

2.1.3 Occupational Medical Doses 

Both DR methods calculated an occupational medical dose from diagnostic x-ray procedures 

required as a condition of employment. NIOSH indicated that they followed guidance cited in 

ORAUT-OTIB-0079 and ORAUT-TKBS-0028-3 in order to calculate their occupational medical 

doses.

SC&A used guidance provided in ORAUT-TKBS-0028-3 and ORAUT-TKBS-0006-3. 

Both NIOSH and SC&A assigned dose for 8 occupational medical x-ray exams during the period 

[redact]–[redact] while the EE was employed at the Weldon Spring Plant. NIOSH and SC&A 

both assumed the exams included PA views plus LAT views. SC&A used the recommended 

exam frequency in Section 3.1.2 and the liver dose values recommended in Table 3-3 of 

ORAUT-TKBS-0028-3. 

In [redact], the EE had a pre-employment photofluorography (PFG) exam at the Hanford Site. 

Exhibit 2-1 shows the radiographic report form from the Hanford Works. SC&A used the dose 

values recommended in Table 3-1 of ORAUT-TKBS-0006-3 to assign a dose to the liver from 

this PFG exam. NIOSH did not assign the Hanford PFG dose, citing guidance in ORAUTOTIB-0079.

Table 2-5 summarizes NIOSH’s and SC&A’s dose assignments. 
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Table 2-5. Comparison of Occupational Medical Doses 

Site NIOSH

(rem)

SC&A

(rem)

Weldon Spring Plant [redact]– [redact] 1.602 1.602

Hanford Site [redact] – 0.690

Total 1.602 2.292

Each DR method entered the annual doses into the IREP Input tables with a normal distribution 

and a standard deviation (SD) of 30%. 

Exhibit 2-1. Hanford PFG Exam 

2.1.4 Onsite Ambient External Dose 

The EE was not monitored for external exposure while at the Hanford Site from [redact], to 

[redact]. Both NIOSH and SC&A assigned ambient external dose for this Hanford time period.

SC&A determined the Hanford ambient dose as follows. Table 4-8 of ORAUT-TKBS-0006-4 

shows 0.115 rem/year as the maximum external gamma dose for [redact]. Using the isotropic 

DCF for the liver of 0.568, correcting for 2,500 hours/year (50 hours/week and 50 occupational 

weeks/year), and prorating for the 3-month time period results in an ambient dose of: 

SC&A ambient dose = Annual Dose × DCF × 2,500/2,000 × 3/12 months 

= 0.115 rem/year × 0.568 × 1.25 × 0.25 year 

= 0.020 rem 

NIOSH determined the Hanford ambient dose using 0.115 rem/yr as the maximum external 

gamma dose for [redact], an isotropic DCF of 1.0, correcting for 2,500 hours/yr (50 hours/week 

and 52 calendar weeks/yr), and prorating for the 3-month time period based on days. 
Effective Date:

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NIOSH ambient dose = Annual Dose × DCF × 2600/2000 × 93/265 days 

= 0.115 rem/year × 1.0× 1.30 × 0.255 year 

= 0.038 rem 

NIOSH used maximizing assumptions for the DCF (1.0 instead of 0.568) and the working hours 

per year (2,600 hours instead of 2,500), while SC&A used best-estimate parameters for 

calculating the Hanford ambient external dose. 

NIOSH also assigned ambient dose for employment at the Weldon Spring Plant during [redact]

and [redact]. The EE began work in [redact]; however, no dosimeter results were found for that 

year. In [redact], the EE was monitored every month except September. Using the 50th

percentile value of the median external doses from Table 4-3 of ORAUT-TKBS-0028-4, NIOSH

calculated onsite ambient doses of 0.043 rem and 0.020 rem for [redact] and [redact], 

respectively.

1957 Ambient dose = (1957 Table 4-3) × DCF × fraction of year 

= 0.161 rem × 1.064 × 0.25 

= 0.043 rem 

Since the EE submitted a bioassay sample in August (pre-hire) and September of [redact], 

SC&A assigned coworker (CW) doses instead of ambient doses. The 50th percentile value of the 

median external doses in [redact] from Table 6-8 of ORAUT-TKBS-0028-6 was used to account 

for any potential dose from [redact], until [redact]. Table 6-8 contains the same external doses 

as Table 4-3. SC&A used the same photon energy distribution and geometric factors as were 

used to assign recorded and missed photon doses.

30–250 keV photon ambient dose = (1957 Table 6-8) × DCF × Energy f. × CF × GCF 

= 0.161 rem × 1.064 × 0.50 × 1.1 × 2.1 

= 0.198 rem 

 >250 keV photon ambient dose = (1957 Table 6-8) × DCF × Energy f. × GCF 

= 0.161 rem × 0.845 × 0.50× 2.1 

= 0.143 rem 

SC&A did not assign unmonitored or ambient dose for September of [redact]. 

Table 2-6. Comparison of Onsite Ambient Doses 

Site NIOSH

(rem)

SC&A

(rem)

Weldon Spring Plant 0.063 0.341

Hanford Site 0.038 0.027

Total 0.101 0.368
Effective Date:

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2.2 OCCUPATIONAL INTERNAL DOSES 

The EE was not monitored for internal exposures while at Hanford in [redact]. According to the 

Special Exposure Cohort (SEC) and the determination by NIOSH, the maximum internal 

exposure cannot be completely reconstructed for some radionuclides through December 31, 

1983. Therefore, the Hanford internal dose was assessed based on reported environmental 

airborne radionuclide concentrations given in Table A-12 of ORAUT-TKBS-0006-4. 

At the Weldon Spring Plant, the EE was monitored for potential internal exposure via urine 

sampling from [redact]–[redact].

2.2.1 Internal Doses from Uranium 

Both SC&A and NIOSH used the EE’s uranium bioassay data to determine the uranium intake. 

The EE was monitored for potential uranium exposure from [redact], through [redact]. Several 

of the urine samples were reported with total uranium concentrations above the minimum 

detectable activity (MDA), of 0.008 micrograms per liter (μg/L). 

SC&A’s Best-Estimate Method 

Prior to [redact], all of the EE’s bioassay results were less than the detection limit. SC&A 

performed a visual fit of the bioassay data using Integrated Modules of Bioassay Analysis

(IMBA) and an assumed chronic intake period from [redact], until the EE’s sample date of 

[redact]. The IMBA-generated uranium-234 intake activity associated with absorption Type M 

was calculated to be 225 pCi/day.

NIOSH’s Overestimating Method 

NIOSH used overestimating assumptions to determine the EE’s uranium intake. A chronic 

intake was calculated throughout the EE’s employment that would have led to the EE’s highest 

bioassay result during employment, which was 0.025 mg/L in a [redact], sample. Intakes of 

lead-210, polonium-210, radium-226, radium-228, thorium-228, thorium-230, and thorium-232 

were calculated as bounding intakes based on the ratios to uranium provided in Table 5-21 of 

ORAUT-TKBS-0028-5, “Intakes of uranium decay products and other impurities based on 

raffinate pit measurements.” 

Table 2-7. NIOSH Uranium and Decay Product Intakes 

Radionuclide Type Start End Intake Unit/Rate

Uranium-234 S [redact] [redact] 5,780 pCi/day

Lead-210 F [redact] [redact] 1,058 pCi/day

Polonium-210 M [redact] [redact] 1,058 pCi/day

Radium-226 M [redact] [redact] 1,058 pCi/day

Radium-228 S [redact] [redact] 42.3 pCi/day

Thorium-228 S [redact] [redact] 33.9 pCi/day

Thorium-230 S [redact] [redact] 2,877 pCi/day

Thorium-232 S [redact] [redact] 50.8 pCi/day
 

 

 

 

 

 

 

 

 

 

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2.2.2 Internal Doses from Recycled Uranium Contaminants 

Both SC&A and NIOSH assigned dose from recycled uranium (RU) contaminants. Recycled 

uranium (RU) was first introduced at the Weldon Spring Plant in 1961. Therefore, all uranium 

intakes after 1960 are assumed to have associated plutonium-239, neptunium-237, and 

technetium-99 intakes. The RU components were added as 100 ppb plutonium-239, 3,500 ppb 

neptunium-237, and 9,000 ppb technetium-99 (ppb = parts per billion) (ORAUT-TKBS-0028-5). 

These are the same RU ratios to uranium listed in Section 5.2.2 of the TBD for the Fernald 

Environmental Management Project (FEMP) – Occupational Internal Dose (ORAUT-TKBS0017-5). 

SC&A’s Best-Estimate Method 

SC&A used the previously determined uranium intake of 225 pCi/day and the FEMP Recycled 

Uranium Mix Intake Rate Calculator 2.00 to determine the RU contaminants intake rates 

assuming natural uranium with RU components in [redact] and [redact], and 1% enriched 

uranium with RU components for [redact] and [redact]. Table 2-8 lists each of the intake 

periods, intake rates and RU:U ratios. 

Table 2-8. SC&A Uranium and RU Contaminant Intakes 

Radionuclide Type Intake Period Intake Rate 

(pCi/day) 

Uranium 

Type RU:U Ratio 

U-234 M [redact]– [redact] 225 – 

Pu-239 M [redact]– [redact] 2.072 

natural 

9.21E-03 

Np-237 M [redact]– [redact] 0.823 3.66E-03 

Tc-99 M [redact]– [redact] 50.850 2.26E-01 

Pu-239 M [redact]– [redact] 1.454 

1% enriched 

6.46E-03 

Np-239 M [redact]– [redact] 0.578 2.57E-03 

Tc-99 M [redact]– [redact] 35.390 1.57E-01 

The Chronic Annual Dose Workbook (CADW), version 8.2.4, and above-cited intake rates were 

used to calculate the doses. The EE’s dose to the liver from uranium and RU processing from 

[redact] through [redact], assuming a full year of exposure for each year, was calculated to be 

2.331 rem. 

NIOSH’s Overestimating Method 

NIOSH used the previously determined uranium intake of 5,780 pCi/day and the RU 

contaminant conversion factors from Table 5-11 of ORAUT-TKBS-0017-5 to determine the RU 

contaminant intake rates. As an overestimate of the RU contaminant intakes, NIOSH assumed a 

uranium intake of natural uranium for the entire time period. Table 2-9 lists each of the intake 

periods, intake rates, and RU:U ratios. 

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution.
 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

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Table 2-9. NIOSH Uranium and RU Contaminant Intakes 

Radionuclide Type Start End Intake Rate 

(pCi/day)

Uranium 

Type RU:U Ratio

U-234 S [redact] [redact] 5,780 –

Pu-239 S [redact] [redact] 0.532

natural

9.20E-04

Np-237 M [redact] [redact] 0.006 1.04E-06

Tc-99 M [redact] [redact] 0.145 2.51E-05

NIOSH used the CADW, version 8.2.4, and intake rates above to calculate the uranium and RU 

doses. NIOSH calculated the EE’s gallbladder dose from uranium and RU processing from 

[redact] through [redact], assuming a full year of exposure for each year, to be 3.215 rem. 

Comparison of the Methods and Results 

Besides the obvious differences in the best-estimate versus overestimate approaches, SC&A 

found two key distinctions. 

1. The RU:U ratios in Tables 2-8 and 2-9 for natural uranium are different for SC&A and 

NIOSH. SC&A used the FEMP Recycled Uranium Mix Intake Rate Calculator 2.00 to 

determine the RU contaminant intake rates shown in Table 2-10. The RU:U ratio is 

simply the RU specific activity divided by the U mixture specific activity. 

Table 2-10. SC&A RU:U Determination 

Radionuclide Specific Activity 

(pCi/mg) RU:U Ratio

U-234 (natural) 683 –

Pu-239 6.289 9.21E-03

Np-237 2.499 3.66E-03

Tc-99 154.35 2.26E-01

It appears the NIOSH dose reconstructor developed a spreadsheet to calculate the RU:U 

ratios in which the ppb conversion factors from Table 5-11 of ORAUT-TKBS-0017-5 

were applied as the specific activities for Pu-239, Np-237, and Tc-99. For example, the 

RU:U ratio for Np-237 was incorrectly calculated as: 

RU:U(Np-237) = 0.714 pCi/g ÷ 683 pCi/mg ÷ 1,000 mg/g 

 = 1.04E-06

The correct RU:U ratio for Np-237 would be: 

RU:U(Np-237) = 2.499 pCi/mg ÷ 683 pCi/mg 

 = 3.66E-03

When applied to NIOSH’s U-234 intake of 5,780 pCi/day gives an Np-237 intake rate of 

21.2 pCi/day instead of 0.006 pCi/day assigned by NIOSH. 

Table 2-11 shows a comparison of the SC&A- and NIOSH-calculated RU-to-U ratios. 
Effective Date:

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Table 2-11. RU:U Comparison 

Radionuclide SC&A RU:U 

Ratio

NIOSH RU:U 

Ratio SC&A/NIOSH

Pu-239 9.21E-03 9.20E-04 10

Np-237 3.66E-03 1.04E-06 3519

Tc-99 2.26E-01 2.51E-05 9003

2. SC&A assigned the dose to the liver, while NIOSH assigned the dose to the gallbladder. 

According to the EE’s DOL initial case file, the EE’s cancer is listed as 

cholangiocarcinoma – bile ducts, ICD-9 Code 155.1. ORAUT-OTIB-0005 states: 

For ICD-9 code 155.1, for cancers that are described as cancer of the 

intrahepatic ducts, select liver as the internal organ. For those that are 

described as gallbladder carcinoma, select gallbladder as the internal organ. 

If the description is unclear, a medical review should be conducted to 

determine the appropriate internal organ of interest.

2.2.3 Internal Doses from Thorium Processing 

Both SC&A and NIOSH assigned dose from thorium processing at the Weldon Spring Plant 

from [redact] through [redact].

SC&A’s Best-Estimate Method 

Inhalation and ingestion intakes of thorium-228, thorium-232, and radium-228 were assigned per 

the guidance of ORAUT-TKBS-0028-5. The Th-232 intake rates were taken from Table 5-22 of 

ORAUT-TKBS-0028-5. Based on Table 5-23 of ORAUT-TKBS-0028-5, the Th-228 activity is 

equal to the Th-232 activity, and the Ra-228 activity is equal to two times the Th-232 activity. 

Intake activities in the table below are in Bq/year. Since the EE terminated in June of [redact], 

SC&A applied one-half the annual intakes for that year. SC&A calculated the EE’s dose to the 

liver from thorium processing in [redact] through [redact] to be 1.734 rem. Table 2-12 shows 

the intakes and doses used by SC&A. 

Table 2-12. SC&A Thorium Processing Intakes 

Radionuclide Type Year Intake Rate 

(Bq/yr) Pathway Dose (rem)

Ra-228 M [redact] 92 Inhalation 7.911E-04

Th-228 M [redact] 46 Inhalation 5.369E-02

Th-232 M [redact] 46 Inhalation 8.794E-02

Ra-228 M [redact] 1,040 Inhalation 8.943E-03

Th-228 M [redact] 520 Inhalation 6.069E-01

Th-232 M [redact] 520 Inhalation 9.750E-01

Ra-228 0.2 [redact] 2 Ingestion 1.748E-05

Th-228 MAX(0.0005) [redact] 1 Ingestion 1.040E-05

Th-232 MAX(0.0005) [redact] 1 Ingestion 1.555E-05

Ra-228 0.2 [redact] 21 Ingestion 1.835E-04

Th-228 MAX(0.0005) [redact] 10.5 Ingestion 1.092E-04

Th-232 MAX(0.0005) [redact] 10.5 Ingestion 1.602E-04
Effective Date:

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NIOSH’s Method 

The DR report states that NIOSH also assigned inhalation and ingestion intakes of thorium-228, 

thorium-232, and radium-228 using the guidance of ORAUT-TKBS-0028-5. NIOSH calculated 

the EE’s dose to the gallbladder from thorium processing as 0.254 rem. Table 2-13 shows the 

intakes and doses used by NIOSH. 

Table 2-13. NIOSH Thorium Processing Intakes 

Radionuclide Type Year Intake Rate 

(Bq/yr) Pathway Dose (rem)

Ra-228 S [redact] 92 Inhalation 9.538E-04

Th-228 MAX(M) [redact] 46 Inhalation 3.555E-03

Th-230 MAX(M) [redact] 46 Inhalation 6.370E-03

Ra-228 S [redact] 2,080 Inhalation 2.156E-02

Th-228 MAX(M) [redact] 1,040 Inhalation 8.037E-02

Th-230 MAX(M) [redact] 1,040 Inhalation 1.404E-01

Ra-228 0.2 [redact] 2 Ingestion 1.877E-05

Th-228 MAX(0.0005) [redact] 1 Ingestion 7.148E-07

Th-230 MAX(0.0005) [redact] 1 Ingestion 1.130E-06

Ra-228 0.2 [redact] 42 Ingestion 3.943E-04

Th-228 MAX(0.0005) [redact] 21 Ingestion 1.501E-05

Th-230 MAX(0.0005) [redact] 21 Ingestion 2.314E-05

Comparison of the Methods and Results 

Considering SC&A applied one-half the annual intake rates for [redact], both SC&A’s and 

NIOSH’s intake rates are similar. However, the doses differ by a factor of 7. The two key 

differences are:

1. SC&A assigned the dose to the liver; NIOSH assigned the dose to the gallbladder. 

2. NIOSH assigned dose from Th-230 instead of Th-232. Row four, column six, of each 

table shows the difference in dose; Th-232/Th-230 = 8.794E-02/6.370E-03 = 13.8. 

2.2.4 Internal Environmental Dose 

Both SC&A and NIOSH assessed internal environmental dose for [redact] while the EE was 

employed at Hanford. In both calculations, the dose from environmental intakes in [redact] was 

determined to be less than 0.001 rem.
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3.0 SUMMARY CONCLUSIONS 

Total external and internal doses and resultant POCs calculated by NIOSH and SC&A in behalf 

of Case #[Redact] are presented in Table 3-1 for comparison. 

Table 3-1. Comparison of Total External and Internal Doses 

Total Dose NIOSH

(rem)

SC&A

(rem)

External Dose: 13.423 9.282

Internal Dose: 6.623 4.065

Total Dose 20.046 13.347

POC 42.49% 40.71%

As shown in Table 3-1, NIOSH’s and SC&A’s methods resulted in individual cancer POCs, and 

a combined total POC, that were nearly identical; NIOSH derived a total combined POC of 

42.49% compared to 40.71% for SC&A. 

The following summarizes/compares the methods used by NIOSH and SC&A to assign doses in 

this case: 

 Dose Reconstruction Methodology 

 – NIOSH used an overestimating approach and SC&A employed a best-estimate 

approach to the dose reconstruction. 

 Assignment of External Dose 

 – NIOSH applied overestimating factors, such as a DCF equal to 1.0 for photons 

greater than 250 keV. SC&A used the photon DCF values in OCAS-IG-001.

NIOSH assigned neutron doses; SC&A did not. 

.

 Assignment of Occupational Medical Dose 

 – NIOSH and SC&A used the same methodology in assigning medical doses for the 

Weldon Spring Plant. NIOSH did not assign a dose for Hanford, while SC&A did 

assign medical dose for the Hanford employment. 

 Assignment of Internal Doses 

 – SC&A employed a best-estimate approach to assigning internal doses. NIOSH used 

an overestimating approach. NIOSH assigned the internal doses to the gallbladder. 

SC&A assigned the internal doses to the liver. 
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REFERENCES 

ICRP (International Commission on Radiological Protection) 1990. Recommendations of the 

International Commission on Radiological Protection, Publication 60, Pergamon Press, Oxford, 

England. 

OCAS-IG-001. 2007. External Dose Reconstruction Implementation Guideline, Rev. 3, 

National Institute for Occupational Safety and Health, Office of Compensation Analysis and 

Support, Cincinnati, Ohio. November 21, 2007. 

ORAUT. 2010. SEC Petition Evaluation Report for the Weldon Spring Plant, Petition SEC00143, Rev. 00, Oak Ridge Associated Universities Team, Cincinnati, Ohio. November 22, 

2010.

ORAUT-OTIB-0005. 2012. Technical Information Bulletin: Internal Dosimetry Organ, 

External Dosimetry Organ, and IREP Model Selection by ICD-9 Code, Rev. 05, Oak Ridge 

Associated Universities Team, Cincinnati, Ohio. December 20, 2012. 

ORAUT-OTIB-0014. 2014. Technical Information Bulletin – Assignment of Environmental 

Internal Doses for Employees Not Exposed to Airborne Radionuclides in the Workplace, 

Rev. 00, Oak Ridge Associated Universities Team, Cincinnati, Ohio. June 22, 2004. 

ORAUT-OTIB-0079. 2011. Technical Information Bulletin: Guidance on Assigning 

Occupational X-Ray Dose under EEOICPA for X-Rays Administered Off Site, Rev. 00, Oak 

Ridge Associated Universities Team, Cincinnati, Ohio. January 3, 2011. 

ORAUT-PROC-0060. 2006. Occupational On-Site Ambient Dose Reconstruction for DOE Sites, 

Rev. 01, Oak Ridge Associated Universities Team, Cincinnati, Ohio. June 28, 2006. 

ORAUT-TKBS-0006-3. 2010. Hanford Site – Occupational Medical Dose, Rev. 03, Oak Ridge 

Associated Universities Team, Cincinnati, Ohio. January 7, 2010. 

ORAUT-TKBS-0006-4. 2010. Hanford Site – Occupational Environmental Dose, Rev. 03, Oak 

Ridge Associated Universities Team, Cincinnati, Ohio. January 7, 2010. 

ORAUT-TKBS-0017-5. 2004. Technical Basis Document for the Fernald Environmental 

Management Project (FEMP) – Occupational Internal Dose, Rev. 00, Oak Ridge Associated 

Universities Team, Cincinnati, Ohio. May 28, 2004. 

ORAUT-TKBS-0028-3. 2013. Weldon Spring Plant – Occupational Medical Dose, Rev. 01,

Oak Ridge Associated Universities Team, Cincinnati, Ohio. January 30, 2013. 

ORAUT-TKBS-0028-4. 2013. Weldon Spring Plant – Occupational Environmental Dose, 

Rev. 01, Oak Ridge Associated Universities Team, Cincinnati, Ohio. May 17, 2013. 
Effective Date:

June 17, 2015

Revision No.

0 (Draft)

Document No. 

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However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

ORAUT-TKBS-0028-5. 2013. Weldon Spring Plant – Occupational Internal Dose, Rev. 02,

Oak Ridge Associated Universities Team, Cincinnati, Ohio. May 21, 2013. 

ORAUT-TKBS-0028-6. 2013. Weldon Spring Plant – Occupational External Dose, Rev. 01,

Oak Ridge Associated Universities Team, Cincinnati, Ohio. February 6, 2013. 
Effective Date:

June 17, 2015

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0 (Draft)

Document No. 

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ADDENDUM A: SC&A’S BLIND DOSE RECONSTRUCTION 

REPORT OF CASE #[REDACT] 
DRAFT 

REPORT TO THE ADVISORY BOARD 

ON RADIATION AND WORKER HEALTH

National Institute of Occupational Safety and Health 

BLIND DOSE RECONSTRUCTION OF CASE #[REDACT]

FROM THE HANFORD AND WELDON SPRING SITES

Contract No. 211-2014-58081 

SCA-TR-BDR2015-CN[Redact]

Prepared by 

Douglas Farver, CHP 

S. Cohen & Associates 

1608 Spring Hill Road, Suite 400 

Vienna, Virginia 22182 

February 2015

Disclaimer

This document is made available in accordance with the unanimous desire of the Advisory Board on 

Radiation and Worker Health (ABRWH) to maintain all possible openness in its deliberations. However, 

the ABRWH and its contractor, SC&A, caution the reader that at the time of its release, this report is predecisional and has not been reviewed by the Board for factual accuracy or applicability within the 

requirements of 42 CFR 82. This implies that once reviewed by the ABRWH, the Board’s position may 

differ from the report’s conclusions. Thus, the reader should be cautioned that this report is for 

information only and that premature interpretations regarding its conclusions are unwarranted.
Effective Date:

February 27, 2015

Revision No.

0 (Draft)

Document No. 

SCA-TR-BDR2015-CN[Redact]

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2 of 19

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S. Cohen & Associates:

Technical Support for the Advisory Board on

Radiation & Worker Health Review of

NIOSH Dose Reconstruction Program

Document No. 

SCA-TR-BDR2015-CN[Redact]

Effective Date: 

Draft – February 27, 2015

Revision No.

0 (Draft)

BLIND DOSE RECONSTRUCTION 

OF CASE #[REDACT] FROM THE HANFORD 

AND WELDON SPRING SITES

Page 2 of 19

Task Manager:

___________________________ Date:

Douglas Farver, CHP

Supersedes:

N/A

Project Manager: 

___________________________ Date:

John Stiver, MS, CHP

Reviewers:

 Kathleen Behling

 Rose Gogliotti

 John Stiver

Record of Revisions

Revision 

Number Effective Date Description of Revision

0 (Draft) 02/27/2015 Initial issued.
Effective Date:

February 27, 2015

Revision No.

0 (Draft)

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TABLE OF CONTENTS 

Abbreviations and Acronyms ......................................................................................................... 4

1.0 Summary Background Information .................................................................................... 6

1.1 SC&A Blind DR Approach .................................................................................... 6

2.0 External Doses .................................................................................................................... 8

2.1 Recorded Photon Doses .......................................................................................... 8

2.2 Coworker Dose ....................................................................................................... 9

2.3 Missed Photon Doses .............................................................................................. 9

2.4 Occupational Medical Dose .................................................................................. 10

2.5 Onsite Ambient Dose ............................................................................................ 10

3.0 Internal Doses ................................................................................................................... 11

3.1 Uranium Intake ..................................................................................................... 11

3.2 Recycled Uranium Contaminant Intakes .............................................................. 12

3.2.1 Insoluble Plutonium .................................................................................. 12

3.3 Thorium Intakes .................................................................................................... 13

3.4 Radon and Thoron................................................................................................. 13

3.5 Environmental Dose.............................................................................................. 13

4.0 CATI Report and Radiological Incidents ......................................................................... 14

5.0 Summary Conclusions ...................................................................................................... 15

References ..................................................................................................................................... 16

Appendix A: IREP Input – Liver ................................................................................................. 17

LIST OF TABLES 

Table 1. Summary of SC&A-Derived External/Internal Dose Estimates .......................................7

Table 2. Uranium Bioassay Results ..............................................................................................11

Table 3. Recycled Uranium Components at WSP ........................................................................12

Table 4. Uranium and RU Contaminant Intakes ...........................................................................12

Table 5. Intakes from Thorium Processing (Bq/year) ..................................................................13
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ABBREVIATIONS AND ACRONYMS 

AP anterior-posterior 

Bq Becquerel 

CADW chronic annual dose workbook 

CATI Computer-Assisted Telephone Interview 

CF correction factor 

CW coworker 

D.D. deep dose 

DCF dose conversion factors 

DOE (U.S.) Department of Energy 

DOL (U.S.) Department of Labor 

dpm disintegrations per minute 

DR dose reconstruction 

EE energy employee 

GF geometric correction factor 

ICD International Classification of Diseases 

ICRP International Commission on Radiological Protection 

IMBA Integrated Modules for Bioassay Analysis 

IREP Interactive RadioEpidemiological Program 

keV kilo electron volt; 1,000 electron volts 

LAT lateral 

LOD limit of detection 

L/day liters per day 

MDA minimum detectable activity 

mg/L milligrams per liter 

μg/L micrograms per liter 

NIOSH National Institute for Occupational Safety and Health 

OCAS Office of Compensation Analysis and Support 

ORAUT Oak Ridge Associated Universities Team 

PA posterior-anterior 

PFG photofluorography 

pC/d picocuries per day 
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pCi/mg picocuries per milligram 

POC probability of causation 

ppb parts per billion 

rem Roentgen equivalent man 

RU recycled uranium 

SC&A S. Cohen and Associates (SC&A, Inc.) 

SpA specific activities 

TBD technical basis document 

U uranium 

yr year 
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1.0 SUMMARY BACKGROUND INFORMATION 

This report presents the results of an independent blind dose reconstruction (DR) performed by 

SC&A for an energy employee (EE) who worked at the Hanford Site from [redact], to [redact],

and at the Weldon Spring Plant from [redact], to [redact]. The EE was diagnosed with bile 

duct cancer (cholangiocarcinoma) (ICD-9 Code 155.1) on [redact].

According to Department of Labor (DOL) files and the Computer-Assisted Telephone Interview 

(CATI) report, the EE was a [redact] at the Hanford Plant and a [redact] at the Weldon Spring 

Plant. The EE was not monitored for external or internal radiation exposure at the Hanford Site. 

However, the EE was monitored for external photon exposure and internal exposures during 

most of the employment period at the Weldon Spring Plant. 

1.1 SC&A BLIND DR APPROACH

SC&A reviewed all of the Department of Energy (DOE) records provided on behalf of this 

employee and the National Institute for Occupational Safety and Health (NIOSH) procedures 

relevant to this case, which included the Technical Basis Document (TBD) for the Hanford Site 

(issued as six separate documents numbered ORAUT-TKBS-0006-1 through ORAUT-TKBS0006-6), the TBD for the Weldon Spring Plant (issued as six separate documents numbered 

ORAUT-TKBS-0028-1 through ORAUT-TKBS-0028-6), ORAUT-OTIB-0005 for surrogate 

organs, OCAS-IG-001 for dose conversion factors (DCFs), and ORAUT-TBKS-0006-3 and 

ORAUT-TKBS-0028-3 for occupational x-ray doses. Using the guidance provided in these 

documents, along with the employee’s dosimetry records, SC&A calculated reasonable, 

claimant-favorable annual organ doses for the liver. Table 1 provides a summary of the total 

doses assigned for the cancer site. Appendix A provides a list of SC&A’s assigned annual organ 

doses and also includes the Interactive RadioEpidemiological Program (IREP) input parameters, 

such as energy range, distribution type, and uncertainty for each year. 
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Table 1. Summary of SC&A-Derived External/Internal Dose Estimates 

IREP Entry Number Dose (rem)

External Dose (Occupational)

 ▪ Recorded/CW:

 30–250 keV Photons 1–6 1.750

 >250 keV Photons 7–12 1.264

 ▪ Missed Dose:

 30–250 keV Photons 13–19 2.010

 >250 keV Photons 20–26 1.598

 ▪ 1957 Coworker Dose:

 30–250 keV Photons 41 0.198

 >250 keV Photons 42 0.143

 ▪ 1948 Onsite Ambient Dose:

 30–250 keV Photons 43 0.027

 ▪ Occupational Medical Dose:

 PFG exam, 1948 44 0.690

 30–250 keV Photons 27–40 1.602

Internal Dose (alpha):

 U, RU, Th 45–86 4.065

Total 13.347

SC&A determined the probability of causation (POC) for this case using the annual doses as 

input into the NIOSH POC program. The total doses shown in Table 1 produced a POC of 

40.71%. 
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2.0 EXTERNAL DOSES 

To perform the external DR, SC&A analyzed the EE’s DOE files containing the dosimeter 

readings and x-ray examinations. Although the EE was employed at the Hanford Site for 

3 months in [redact], no dosimeter or x-ray examination records were found. Dosimetry and 

x-ray exam records were available for the time the EE was employed at the Weldon Spring Plant, 

[redact], to [redact]. Individual dosimeter results or quarterly dosimeter totals are available for 

[redact]– [redact]; however, no dosimeter results were found for [redact].

SC&A used the DR parameters as recommended in ORAUT-TKBS-0028-6, which consisted of 

an energy range of 50% 30–250 keV photons, 50% >250 keV photons (Table 6-10), and a limit 

of detection (LOD) value of 0.050 rem for photons (Table 6-13, page 27). Exposure (as opposed 

to deep dose) conversion factors (DCFs) from OCAS-IG-001 were used to calculate the external 

dose to the liver. For anterior-posterior (AP) geometry, a 30–250 keV photon DCF of 1.064 and 

a >250 keV photon DCF of 0.845 were used. 

2.1 RECORDED PHOTON DOSES 

No dosimetry data were available for the EE’s employment at the Hanford Site in [redact]. The 

EE was employed at the Weldon Spring Plant from [redact], to [redact]. Monitoring records for 

the EE begin in [redact]. SC&A used the recorded photon dose values that were >LOD/2 of 

0.025 rem to assign photon doses using the parameters previously described. A dosimeter 

correction factor (CF) of 1.1 (for 30–250 keV photons only) and geometric correction factor of 

2.1 were also included. ORAUT-TKBS-0028-6 states:

6.3.11 Geometric Correction Factor 

Consideration should be given to geometry when performing dose reconstruction 

for uranium facility workers who worked with uranium metals, powders, or 

residues or for workers who worked on equipment contaminated with uranium. 

An underestimation of the measured and missed photon doses could occur if the 

energy employee wore their dosimeter on the upper chest or lapel and not in the 

central area of the chest or on the waist. The organs located in the lower torso 

region are most affected. These include, but are not limited to, the stomach, liver, 

kidney, ureter, gall bladder, pancreas, small intestine, large intestine, rectum, 

ovaries, uterus, urinary bladder, and prostate. 

Example of [redact] recorded photon dose calculations – SC&A calculated the recorded 

[redact] photon dose to the liver as follows:

Records show in [redact] the EE received a deep dose of 0.490 rem. The photon dose was 

assumed to be 50% 30–250 keV and 50% >250 keV. DCFs of 1.064 for 30–250 keV 

photons and 0.845 for >250 keV photons were applied. Dosimeter and geometric correction 

factors were also applied.

30–250 keV photon dose = D.D. × DCF × Energy f. × CF × GF 

= 0.490 × 1.064 × 0.50 × 1.1 × 2.1 

= 0.602 rem 
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 >250 keV photon dose = D.D. × DCF × Energy f. × GF 

= 0.490 × 0.845 × 0.50 × 2.1 

= 0.435 rem 

SC&A’s calculated [redact] 30–250 keV, and >250 keV doses are shown as IREP entries #3 and

#9, respectively, in Appendix A. SC&A assigned a total of 3.013 rem recorded dose, as shown 

in IREP entries #1–#12 of Appendix A.

2.2 COWORKER DOSE 

The EE was not monitored for external radiation in [redact]. The 50th percentile value of the 

median external doses in [redact] from Table 6-8 of ORAUT-TKBS-0028-6 was used to account 

for any potential dose from [redact], until [redact].

Example of [redact] coworker dose calculations – SC&A calculated the [redact] coworker dose 

to the liver as follows:

The [redact] 50th percentile photon dose is 0.161 rem. The photon dose was assumed to be 

50% 30–250 keV and 50% >250 keV. DCFs of 1.064 for 30–250 keV photons and 0.845 for 

>250 keV photons were applied. Dosimeter and geometric correction factors were also 

applied.

30–250 keV photon dose = D.D. × DCF × Energy f. × CF × GF 

= 0.161 × 1.064 × 0.50 × 1.1 × 2.1 

= 0.198 rem 

 >250 keV photon dose = D.D. × DCF × Energy f. × GF 

= 0.161 × 0.845 × 0.50 × 2.1 

= 0.143 rem 

SC&A’s calculated [redact] 30–250 keV and >250 keV doses are shown as IREP entries #41

and #42, respectively, in Appendix A. SC&A assigned a total of 0.341 rem coworker photon

dose.

2.3 MISSED PHOTON DOSES 

SC&A analyzed the number of physical zeros and potential zeros based on a monthly badge 

exchange cycle using the guidance in OCAS-IG-001and a best-estimate reasonable approach to 

arrive at a total 72 zeros, or <LOD/2 values, for photons. SC&A used the annual number of 

zeros, the LOD/2 value, the DR parameters as listed above, and the applicable DCF to determine 

the annual missed photon dose. 

Example of [redact] missed photon dose calculations – SC&A calculated the missed [redact]

photon dose to the liver as follows:
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In [redact], the EE’s dosimeter results showed 10 zeros. The photon dose was assumed to be 

50% 30–250 keV and 50% >250 keV. DCFs of 1.064 for 30–250 keV photons and 0.845 for 

>250 keV photons were applied. A geometric correction factor was also applied.

Missed Photon Dose (30–250 keV) = (# zeros × LOD/2) × DCF × Energy f × GF 

 = (10 × 0.025 rem) × 1.064 × 0.50 × 2.1 

 = 0.279 rem 

Missed Photon Dose (>250 keV) = (# zeros × LOD/2) × DCF × Energy f. × GF 

= (10 × 0.025 rem) × 0.845 × 0.50 × 2.1 

 = 0.222 rem 

SC&A’s calculated 30–250 keV missed photon dose of 0.279 rem is shown in entry #14 and the 

>250 keV missed photon dose of 0.222 is shown in entry #21 of Appendix A. SC&A assigned a 

total of 3.608 rem missed dose, as shown in IREP entries #13–#26 of Appendix A. 

2.4 OCCUPATIONAL MEDICAL DOSE 

The DOE records show that the EE received one photofluorography (PFG) x-ray exam in 

[redact] at the Hanford Site and eight occupational medical x-ray exams (which were not for 

injuries, etc.) during the period [redact]– [redact]. Posterior-anterior (PA) views plus lateral 

(LAT) views were assumed for all eight exams, per Section 3.1.2 of ORAUT-TKBS-0028-3. 

Using the liver organ dose values recommended in Table 3-1 of ORAUT-TKBS-0006-3 and 

Table 3-3 of ORAUT-TKBS-0028-3 as a function of the year the exam was performed, SC&A 

assigned a dose of 0.690 rem for the PFG exam in entry #44 of the IREP Input table, a total dose 

of 0.722 rem for the PA views (entries #27–#33), and 0.880 rem for the LAT views (entries #34–

#40), for a total occupational medical x-ray dose of 2.292 rem. These doses are summarized in 

Table 1 above, and detailed in Appendix A. 

2.5 ONSITE AMBIENT DOSE 

The EE was not monitored while at the Hanford Site from [redact], to [redact]. Since the EE 

was monitored at the Weldon Spring Plant, external ambient dose should not be applied, in 

accordance with ORAUT-PROC-0060. Therefore, external ambient dose was assigned for the 

time period at the Hanford Site and not assigned while employed at the Weldon Spring Plant. 

The Hanford ambient dose was determined as follows.

Table 4-8 of ORAUT-TKBS-0006-4 shows the 0.115 rem/yr as the maximum external gamma 

dose for [redact]. Using the isotropic DCF for the liver of 0.568, correcting for 2,500 hours/yr, 

and prorating for the 4-month time period, an ambient dose was calculated as follows: 

Ambient dose = Annual Dose × DCF × 2,500/2,000 × 4/12 months

= 0.115 rem/yr × 0.568 × 1.25 × 0.333 yr 

= 0.027 rem 

This value is shown as IREP entry #43 of Appendix A. 
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The EE’s internal dose monitori

3.0 INTERNAL DOSES 

ng records were reviewed and showed the EE was not monitored 

for internal exposures while at Hanford in [redact]. At the Weldon Spring Plant, the EE was 

monitored for potential uranium exposure via urine samples. In addition to uranium exposure, 

exposures to thorium and radon were considered. 

3.1 URANIUM INTAKE 

While employed at Weldon Spring, the EE was monitored for potential uranium exposure via 

urine samples that were submitted from [redact], through [redact]. Several of the urine samples 

were reported with total uranium concentrations above the minimum detectable activity (MDA) 

of 0.008 micrograms per liter (μg/L). As specified in the Weldon Spring TBD (ORAUT-TKBS0028-5), the assumed specific activities (SpA) used in this assessment were natural uranium 

(specific activity = 683 pCi/mg) for the years [redact] through [redact], natural uranium with 

recycled uranium (RU) components in [redact] and [redact], and 1% enriched uranium 

(0.973 pCi/mg) from Table 5-3 of the Fernald Environmental Management Project TBD 

(ORAUT-TKBS-0017-5) with RU components for [redact]. The uranium activities were 

normalized to a daily urine excretion rate of 1.4 L/day, and the uranium intakes were assessed as 

100% uranium-234. Table 2 shows the EE’s bioassay results. 

Table 2. Uranium Bioassay Results 

Date

[redact]

Result 

(mg/L)

0.04+

pCi/d*

34.42+

MDA 

pCi/d*

7.87

Date

[redact] 

Result 

(mg/L)

0.02

pCi/d* MDA 

pCi/d*

7.87

[redact] 0.00 0.98 7.87 [redact] 0.01 13

17.70

.77 7.87

[redact] 0.00 0.00 7.87 [redact] 0.01 4.92 7.87

[redact] 0.00 1.97 7.87 [redact] 0.01 8.85 7.87

[redact] 0.00 3.93 7.87 [redact] 0.01 7.87 7.87

[redact] 0.00 3.93 7.87 [redact] 0.02 19.67 7.87

[redact] 0.00 1.97 7.87 [redact] 0.02 20.30 9.02

[redact] 0.00 2.95 7.87 [redact] 0.01 15.79 9.02

[redact] 0.01 9.84 7.87 [redact] 0.02 21.42 9.02

[redact] 0.01 4.92 7.87 [redact] 0.01 15.79 9.02

[redact] 0.00 3.93 7.87 [redact] 0.01 7.89 9.02

[redact] 0.01 11.80 7.87 [redact] 0.00 0.00 9.02

[redact] 0.02 19.67 7.87 [redact] 0.02 20.30 9.02

[redact] 0.00 1.97 7.87 [redact] 0.00 4.51 9.02

[redact] 0.02 18.69 7.87 [redact] 0.03 28.19 9.02

[redact] 0.00 2.95 7.87 [redact] 0.02 24.81 9.02

[redact] 0.01 10.82 7.87 [redact] 0.01 9.02 9.02

[redact] 0.02 21.64 7.87 [redact] 0.01 9.02 9.02

+

[redact] 0.02 16.72 7.87 [redact] 0.01 7.89 9.02

 Sample is prior to employment date and not included in the intake assessment 

* Daily intake based on SpA for natural uranium of 683 pCi/mg through [redact] and SpA of 1% enriched uranium of 

783 pCi/mg for [redact] and later
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Prior to [redact], all of the EE’s bioassay results were less than the detection limit. A visual fit 

of the bioassay results was performed using the Integrated Modules for Bioassay Analysis 

(IMBA) program and an assumed chronic intake period from [redact], until the EE’s sample 

date of [redact]. The IMBA-generated uranium-234 intake activity associated with absorption 

Type M was calculated to be 225 pCi/d.

3.2 RECYCLED URANIUM CONTAMINANT INTAKES 

Recycled uranium (RU) was first introduced at the Weldon Spring Plant in 1961. Therefore, all 

uranium intakes after 1960 are assumed to have associated plutonium-239, neptunium-237, and 

technetium-99 intakes. The RU components were added as 100 ppb plutonium-239, 3,500 ppb 

neptunium-237, and 9,000 ppb technetium-99 (ORAUT-TKBS-0028-5). The ratios of RU

contaminants to uranium (dpm/dpm U) were calculated and are shown in Table 3. 

Table 3. Recycled Uranium Components at WSP 

Contaminant:Uranium Ratio

RU Contaminant Natural U 1% Enriched U

Plutonium-239 9.21E-03 6.46E-03

Neptunium-237 3.66E-03 2.57E-03

Technetium-99 2.26E-01 1.57E-01

The previously determined uranium intake, 225 pCi/d, and the ratios above were used to 

calculate daily intakes for each of the contaminants based on natural uranium in [redact] and 1% 

enriched uranium in [redact] and [redact]. Table 4 lists each of the intake periods and intake 

rates. 

Table 4. Uranium and RU Contaminant Intakes 

Radionuclide Intake Period Intake Rate (pCi/d)

U-234 M [redact]–[redact] 225

Pu-239 M [redact]–[redact] 2.072

Np-237 M [redact]–[redact] 0.823

Tc-99 M [redact]–[redact] 50.850

Pu-239 M [redact]–[redact] 1.454

Np-239 M [redact]–[redact] 0.578

Tc-99 M [redact]–[redact] 35.390

The Chronic Annual Dose Workbook (CADW), version 8.2.4, and intake rates were used to 

calculate the doses. The EE’s dose to the liver from U and RU processing from [redact] through 

[redact], assuming a full year of exposure for each year, was calculated to be 2.331 rem. 

3.2.1 Insoluble Plutonium 

Some forms of plutonium exhibit longer lung clearance times than those used in the International 

Commission on Radiological Protection Publication 66 (ICRP 1994) model for insoluble 

(Type S) plutonium. This can result in higher doses to some organs, so dose modification factors 

were developed, as described in ORAUT-OTIB-0049, Technical Information Bulletin: 

Estimating Doses for Plutonium Strongly Retained in the Lung. The EE’s dose is estimated to 
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the liver, a systemic organ (portions of the body not included in the respiratory or gastrointestinal 

tracts), using air concentrations. The dose to a systemic organ from an inhalation of plutonium is 

the result of plutonium that is absorbed into the bloodstream. Because Type Super S plutonium 

is retained in the lungs for a longer time than more soluble forms of plutonium (Types M and S), 

less is transferred to the blood, and hence the dose is lower than for an equal intake of Type M or 

Type S plutonium. Therefore, dose adjustments for plutonium (plutonium-239 and its mixtures) 

strongly retained in the lung (Type Super S) are not required for the dose to the liver. 

3.3 THORIUM INTAKES 

To account for the EE’s potential internal dose due to thorium processing at the Weldon Spring 

Plant from [redact] through [redact], inhalation and ingestion intakes of thorium-228, 

thorium-232, and radium-228 were also assigned, per the guidance of the ORAUT-TKBS-0028-

5. The solubility was selected to maximize the dose to the liver. The Th-232 intake rates shown 

in Table 5 were taken from Table 5-22 of ORAUT-TKBS-0028-5. Based on Table 5-23 of 

ORAUT-TKBS-0028-5, the Th-228 activity is equal to Th-232 activity and Ra-228 activity is 

equal to two times Th-232 activity, when more than one type may have been present. Intake 

activities in Table 5 are in Bq/year. 

Table 5. Intakes from Thorium Processing (Bq/year) 

Year Th-228 M Th-228 Th-232 M Th-232 Ra-228 M Ra-228

Inhalation Ingestion Inhalation Ingestion Inhalation Ingestion

[redact] 46 1 46 1 92 2

[redact] 1040 21 1040 21 2080 42

The CADW tool was used to calculate the thorium doses, assuming a full year of exposure in 

[redact] and partial year of exposure in [redact]. The dose to the liver from thorium processing 

from [redact] through [redact], assuming a half year of exposure in [redact], was calculated to 

be 1.734 rem. 

3.4 RADON AND THORON 

Because of the nature of the EE’s cancer, exposure from radon and thoron was assessed, but not 

assigned in the DR, as it would not result in a significant dose to the liver. 

3.5 ENVIRONMENTAL DOSE 

While employed at Hanford during [redact], the EE was potentially exposed to environmental 

internal exposures. SC&A used the CADW tool and intake information from Table A-12 of 

ORAUT-TKBS-0006-4 to derive the environmental intakes and resulting doses. The annual 

dose for [redact] from environmental intakes was less than 0.001 rem and not included in the 

final IREP Input table.
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4.0 CATI REPORT AND RADIOLOGICAL INCIDENTS 

SC&A reviewed the EE’s DOE records and CATI report to determine if the EE was involved in 

any radiological incidents. SCA& did not find any documentation of radiological incidents that 

would impact the radiation doses assigned in this case. 
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5.0 SUMMARY CONCLUSIONS 

This DR used best-estimate methods to obtain reasonable external and internal dose assignments. 

The derived total doses provided for a POC <50%. 

The total POC for the bile duct cancer was calculated using the NIOSH-Interactive 

RadioEpidemiological Program (v.5.7.1) and determined to be 45.63%.
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REFERENCES 

ICRP (International Commission on Radiological Protection), 1994. Human Respiratory Tract 

Model for Radiological Protection, Publication 66, Pergamon Elsevier Science Inc., Tarrytown, 

New York. 

OCAS-IG-001. 2007. External Dose Reconstruction Implementation Guideline, Rev. 3, 

National Institute for Occupational Safety and Health, Office of Compensation Analysis and 

Support, Cincinnati, Ohio. November 21, 2007. 

ORAUT-OTIB-0005. 2011. Technical Information Bulletin: Internal Dosimetry Organ, 

External Dosimetry Organ, and IREP Model Selection by ICD-9 Code, Rev. 04, Oak Ridge 

Associated Universities Team, Cincinnati, Ohio. April 18, 2011. 

ORAUT-OTIB-0049. 2010. Technical Information Bulletin: Estimating Doses for Plutonium 

Strongly Retained in the Lung, Rev. 01 PC-2. Oak Ridge Associated Universities Team, 

Cincinnati, Ohio. November 29, 2010. 

ORAUT-PROC-0060. 2006. Occupational On-Site Ambient Dose Reconstruction for DOE Sites, 

Rev. 01. Oak Ridge Associated Universities Team, Cincinnati, Ohio. June 28, 2006. 

ORAUT-TKBS-0006-3. 2010. Hanford Site – Occupational Medical Dose, Rev. 03. Oak 

Ridge Associated Universities Team, Cincinnati, Ohio. January 7, 2010. 

ORAUT-TKBS-0006-4. 2010. Hanford Site – Occupational Environmental Dose, Rev. 03. 

Oak Ridge Associated Universities Team, Cincinnati, Ohio. January 7, 2010. 

ORAUT-TKBS-0017-5. 2004. Technical Basis Document for the Fernald Environmental 

Management Project (FEMP) – Occupational Internal Dose, Rev. 00. Oak Ridge Associated 

Universities Team, Cincinnati, Ohio. May 28, 2004. 

ORAUT-TKBS-0028-3. 2013. Weldon Spring Plant – Occupational Medical Dose, Rev. 01. 

Oak Ridge Associated Universities Team, Cincinnati, Ohio. January 30, 2013. 

ORAUT-TKBS-0028-5. 2013. Weldon Spring Plant – Occupational Internal Dose, Rev. 02. 

Oak Ridge Associated Universities Team, Cincinnati, Ohio. May 21, 2013. 

ORAUT-TKBS-0028-6. 2013. Weldon Spring Plant – Occupational External Dose, Rev. 01. 

Oak Ridge Associated Universities Team, Cincinnati, Ohio. February 6, 2013. 
Effective Date:

February 27, 2015

Revision No.

0 (Draft)

Document No. 

SCA-TR-BDR2015-CN[Redact]

Page No.

17 of 19

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

APPENDIX A: IREP INPUT – LIVER 

CLAIMANT CANCER DIAGNOSES

Primary Cancer #1

Primary Cancer 

#2

Primary Cancer 

#3

Secondary 

Cancer #1

Secondary 

Cancer #2

Secondary 

Cancer #3

Cancer Type

Intrahepatic Bile 

Ducts N/A N/A N/A N/A N/A

Date of Diagnosis [redact] N/A N/A N/A N/A N/A

EXPOSURE INFORMATION

Number of exposures

87

Exposure 

#

Exposure 

Year

Exposure 

Rate Radiation Type

Dose 

Distribution 

Type

Parameter 

1

Parameter 

2

Parameter 

3

1 [redact] acute photons E=30–250 keV Constant 0.042 0.000 0.000

2 [redact] acute photons E=30–250 keV Constant 0.091 0.000 0.000

3 [redact] acute photons E=30–250 keV Constant 0.602 0.000 0.000

4 [redact] acute photons E=30–250 keV Constant 0.684 0.000 0.000

5 [redact] acute photons E=30–250 keV Constant 0.244 0.000 0.000

6 [redact] acute photons E=30–250 keV Constant 0.086 0.000 0.000

7 [redact] acute photons E>250 keV Constant 0.030 0.000 0.000

8 [redact] acute photons E>250 keV Constant 0.066 0.000 0.000

9 [redact] acute photons E>250 keV Constant 0.435 0.000 0.000

10 [redact] acute photons E>250 keV Constant 0.494 0.000 0.000

11 [redact] acute photons E>250 keV Constant 0.177 0.000 0.000

12 [redact] acute photons E>250 keV Constant 0.062 0.000 0.000

13 [redact] acute photons E=30–250 keV Lognormal 0.698 1.520 0.000

14 [redact] acute photons E=30–250 keV Lognormal 0.279 1.520 0.000

15 [redact] acute photons E=30–250 keV Lognormal 0.335 1.520 0.000

16 [redact] acute photons E=30–250 keV Lognormal 0.195 1.520 0.000

17 [redact] acute photons E=30–250 keV Lognormal 0.223 1.520 0.000

18 [redact] acute photons E=30–250 keV Lognormal 0.168 1.520 0.000

19 [redact] acute photons E=30–250 keV Lognormal 0.112 1.520 0.000

20 [redact] acute photons E>250 keV Lognormal 0.555 1.520 0.000

21 [redact] acute photons E>250 keV Lognormal 0.222 1.520 0.000

22 [redact] acute photons E>250 keV Lognormal 0.266 1.520 0.000

23 [redact] acute photons E>250 keV Lognormal 0.155 1.520 0.000

24 [redact] acute photons E>250 keV Lognormal 0.178 1.520 0.000

25 [redact] acute photons E>250 keV Lognormal 0.133 1.520 0.000

26 [redact] acute photons E>250 keV Lognormal 0.089 1.520 0.000

27 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

28 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

29 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

30 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

31 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

32 [redact] acute photons E=30–250 keV Normal 0.090 0.027 0.000

33 [redact] acute photons E=30–250 keV Normal 0.180 0.054 0.000
Effective Date:

February 27, 2015

Revision No.

0 (Draft)

Document No. 

SCA-TR-BDR2015-CN[Redact]

Page No.

18 of 19

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

Appendix A: IREP Input – Liver (continued) 

Exposure 

#

Exposure 

Year

Exposure 

Rate Radiation Type

Dose 

Distribution 

Type

Parameter 

1

Parameter 

2

Parameter 

3

34 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

35 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

36 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

37 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

38 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

39 [redact] acute photons E=30–250 keV Normal 0.110 0.033 0.000

40 [redact] acute photons E=30–250 keV Normal 0.220 0.066 0.000

41 [redact] acute photons E=30–250 keV Constant 0.198 0.000 0.000

42 [redact] acute photons E>250 keV Constant 0.143 0.000 0.000

43 [redact] chronic photons E=30–250 keV Constant 0.027 0.000 0.000

44 [redact] acute photons E=30–250 keV Normal 0.690 0.207 0.000

45 [redact] chronic alpha Lognormal 0.005 3.000 0.000

46 [redact] chronic alpha Lognormal 0.018 3.000 0.000

47 [redact] chronic alpha Lognormal 0.041 3.000 0.000

48 [redact] chronic alpha Lognormal 0.072 3.000 0.000

49 [redact] chronic alpha Lognormal 0.202 3.000 0.000

50 [redact] chronic alpha Lognormal 0.302 3.000 0.000

51 [redact] chronic alpha Lognormal 0.243 3.000 0.000

52 [redact] chronic alpha Lognormal 0.198 3.000 0.000

53 [redact] chronic alpha Lognormal 0.168 3.000 0.000

54 [redact] chronic alpha Lognormal 0.148 3.000 0.000

55 [redact] chronic alpha Lognormal 0.134 3.000 0.000

56 [redact] chronic alpha Lognormal 0.124 3.000 0.000

57 [redact] chronic alpha Lognormal 0.116 3.000 0.000

58 [redact] chronic alpha Lognormal 0.111 3.000 0.000

59 [redact] chronic alpha Lognormal 0.106 3.000 0.000

60 [redact] chronic alpha Lognormal 0.102 3.000 0.000

61 [redact] chronic alpha Lognormal 0.099 3.000 0.000

62 [redact] chronic alpha Lognormal 0.096 3.000 0.000

63 [redact] chronic alpha Lognormal 0.093 3.000 0.000

64 [redact] chronic alpha Lognormal 0.090 3.000 0.000

65 [redact] chronic alpha Lognormal 0.088 3.000 0.000

66 [redact] chronic alpha Lognormal 0.086 3.000 0.000

67 [redact] chronic alpha Lognormal 0.084 3.000 0.000

68 [redact] chronic alpha Lognormal 0.082 3.000 0.000

69 [redact] chronic alpha Lognormal 0.080 3.000 0.000

70 [redact] chronic alpha Lognormal 0.078 3.000 0.000

71 [redact] chronic alpha Lognormal 0.076 3.000 0.000

72 [redact] chronic alpha Lognormal 0.074 3.000 0.000

73 [redact] chronic alpha Lognormal 0.073 3.000 0.000

74 [redact] chronic alpha Lognormal 0.071 3.000 0.000

75 [redact] chronic alpha Lognormal 0.069 3.000 0.000

76 [redact] chronic alpha Lognormal 0.068 3.000 0.000
Effective Date:

February 27, 2015

Revision No.

0 (Draft)

Document No. 

SCA-TR-BDR2015-CN[Redact]

Page No.

19 of 19

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

Appendix A: IREP Input – Liver (continued) 

Exposure 

#

Exposure 

Year

Exposure 

Rate Radiation Type

Dose 

Distribution 

Type

Parameter 

1

Parameter 

2

Parameter 

3

77 [redact] chronic alpha Lognormal 0.067 3.000 0.000

78 [redact] chronic alpha Lognormal 0.065 3.000 0.000

79 [redact] chronic alpha Lognormal 0.064 3.000 0.000

80 [redact] chronic alpha Lognormal 0.063 3.000 0.000

81 [redact] chronic alpha Lognormal 0.061 3.000 0.000

82 [redact] chronic alpha Lognormal 0.060 3.000 0.000

83 [redact] chronic alpha Lognormal 0.059 3.000 0.000

84 [redact] chronic alpha Lognormal 0.058 3.000 0.000

85 [redact] chronic alpha Lognormal 0.057 3.000 0.000

86 [redact] chronic alpha Lognormal 0.056 3.000 0.000

87 [redact] chronic alpha Lognormal 0.055 3.000 0.000